OK, I will ask the obvious question. If a control surface weighs 4-6 ozs and with the linkage and control moment, the torque implied to the servo may be 10 ozin of force. Most digitals will put out over 100ozin of torque. Only 10% or less of the total working torque is used to offset the weight of the control surface. The holding torque is 2-3 times the working torque so what is the big need to balance the control surfaces????

...wait...wait...flame suit on.... OK, I am ready!